When Julie Philbrook leads a seminar on bicycle safety, she can count on encountering some people who don't think they need to listen because they're good bikers.

"You might be a very good rider," responds the trauma prevention specialist at Hennepin County Medical Center. "But what are you going to do when the driver of a car makes a mistake? You can get hurt through no fault of your own."

Although bicycles have become a year-round form of transportation, usage spikes in the summer. And so does the number of accidents. Not only are there more riders, but -- as opposed to the serious bikers who keep pedaling all winter -- warm weather attracts casual cyclists, many of whom are not as knowledgeable about the laws and procedures in place to enhance safety.

"A lot of people do not ride safely," said Dorian Grilley, executive director of the Bicycle Alliance of Minnesota. "The vast majority of people are not confident riding on the street. Bikers fare best when they act as and are treated as drivers of vehicles, and that means following the rules of the road."

Despite the cliché about never forgetting how to ride a bike, Grilley's group is convinced that an occasional refresher course can save lives. It sponsors a series of such classes, including one titled Traffic Skills 101 (www.bikemn.org).

In addition to learning the laws, he recommends following three basic guidelines: "Be predictable. Be visible. Be courteous."

No matter how experienced a biker is, Philbrook adamantly recommends wearing a helmet.

"We can fix most other injuries, including broken bones," she said. "But we can't fix brain injuries."

Safety experts consider helmets so important that Nice Ride Minnesota is planning to give away 10,000 helmets over the next two years.

"We're going give out helmets to as many people as we can," said Ellen Apel, the marketing manager. Details about the giveaway events will be posted on the organization's Facebook page.

Here are some other safety tips gleaned from the experts:

• Make yourself visible. Wear bright clothing during the day and a reflective vest at night. Lights also are required at night. Lamps that can be mounted on helmets are gaining favor because, unlike a bike light that points only straight ahead, helmet lights can be directed wherever a biker wants.

• Pretend that you're invisible. Assume that drivers don't see you, which means approaching every encounter from the perspective that you will have to avoid the vehicle rather than expecting the driver to avoid you. And don't think that just because you're riding in a designated bike lane that you can quit worrying about cars.

• Signal your turns. Don't expect drivers to anticipate where you're going. And remember that a bicycle can change directions much faster than a car, so give drivers ample warning.

• Ride with the traffic. Drivers don't anticipate fast-moving traffic coming at them from the other direction, so they're not going to be looking for you.

• Leave the headphones and earbuds at home. Sounds provide valuable information about what's going on around you, including vehicles that are approaching from behind.

• Learn the laws. The website maintained by the state-run Minnesota Share the Road project (www.sharetheroadmn.org)includes links to two versions. You can see thumbnail descriptions of eight of the most commonly encountered laws, or you can click on the entire text of the state statutes.

• Always wear a helmet, and make sure it fits properly. It should be snug and ride flat on the head in line with the eyebrows. "Don't push it back like a cap or you're exposing the front of your head" to an impact, Philbrook said.

And don't be vain about putting it on. When bicyclists tell her that they don't want to wear a helmet because it messes up their hair, Philbrook has a standard response. "When you come into the emergency room after a crash, we won't mess up your hair," she promises. "We'll just shave it off."

Minneapolis performing artist Patrick Scully brings the Mississippi River Boat Ballet to the festival. No art form requires more precision than ballet, so it's anyone's guess how Scully plans to keep nearly 50 boats; sailboats, kayaks, rowing shells, even a couple of bicycle-powered pontoons in balance, here are highlights from the rehearsal.